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Topic: Water chemistry issue...i think (Read 1837 times)

I have read, re-read and tinkered some and tinkered more. Now I am going back to ground zero and asking for some help.

The brews I have success with are IPAs, Saison, Gruits, Kolsch, Trippels, Wits, and Hefes. But every time I try to do a porter or stout the result is astrigent, maybe somewhat tannic or on the other end of the spectrum at thin brown water.

I am NOT doing a unique mashing schedule, very straight forward.

I would like to do a strong brew that includes 4% special B and 2% dehusked carafa III, but gotta admit i'm a little gun shy at this point when it comes to dark special grains and darker beers.

Here is my water profile:

Calcium carbonate ppm= 62 avg, 52-70 range

Magnesium(mg) ppm= 8.8, 7.5-10.3 range

Sodium(na) ppm= 18 avg., 14-24 range

Sulfate(so4) ppm= 7 avg., 4-18 range

Chloride(cl) ppm= 27 avg, 21-34 range

Bicarbonate(hco3)ppm= 34.16

Alkliny = 56 avg, 47-72 range

Total hardness = 3.6 grains/gal avg, 3.0-4.1 range

pH = 8.1-8.3 for SCWA water.

What type of additions/adjustments do you suggest? I really would like to incorprate an imperial stout and porters into my brewing schedule.

IMO you're lucky to be able to brew lower SRM beers with your water- I have to brew darker beers with mine. So to brew your porters and stouts you probably will need to add calcium carbonate to the mash.

Good luck- hope this helps.

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Well, I note that there is something very wrong with the reported ion concentrations since the ions don't balance. I'm pretty sure the bicarbonate concentration is low since the alkalinity suggests that it should be at least 68 ppm. The other thing that was confusing was the reporting of CaCO3 instead of just Ca. It appears that the Ca content is probably around 18 ppm since the hardness is reported around 3.6 grains/gal, which is fairly soft. The Ca content would be about 29 percent of the CaCO3 concentration based on molarity.

These results then balance reasonably well and the corresponding RA calculates at about 55 ppm. This may be marginal for a really pale beer, but OK for amber to brown beers and not too good for black beers.

Phil's report that he ends up with sharp and thin dark beers is just another case in point for my contention that you MUST adjust RA to suit the beer color to produce great beer. With a RA of 55, his water would create pretty low mash pH which sharpens the flavor (acidifies) and pushes the enzymes to create a more attenuable wort. Neither of which adds to a good perception of a beer created that way. There is no need to adjust your brewing water RA if you only want to make passible beer or OK beer. Your choice.

Now, you may recall that Guinness does purposely acidify their stout with sour beer. But you should also recognize that they add this soured beer AFTER fermentation. This avoids the thinning action that would happen if they tried to acheive their preferred finished beer pH by adjusting their mash and wort pH lower.

Back to Phil's question. He should be adding alkalinity to only the mash water to properly buffer the mash pH. I calculate that he would be adding about 0.4 grams of chalk per gallon of mash water or he could add about 0.3 grams of chalk and 0.1 grams of baking soda per gallon of mash water. That will bring the RA into the 130 ppm range, which is about the minimum I recommend for black beers. I recommend that the chalk addition be limited to less than 0.6 grams per gallon of mash water if he finds that he still doesn't like the acidity and body of beers brewed with the previous amounts. Phil still needs to acidify his sparge water to bring the pH down around 5.7 to 6 and avoid tannin extraction. Don't add chalk or baking soda to sparge water. That amount of lactic acid to achieve the pH goal is about 0.3 mL per gallon of sparge water and he should be doing this for all his beers.

There have been several discussions about how some spreadsheets or nomographs guide brewers to overdo their water chemistry and make soda-water tasting beers. Its unfortunate that one source has spawned this flawed guide that has now been taken up by several of the water spreadsheets out there. But, that is not to say that the approach to pairing mash water RA to beer color shouldn't be used. It only needs refinement. My research of the waters from historical brewing centers and waters around the world has led me to recommend that the proper relationship between beer color and RA is approximately RA = SRM times 4.5. My research also indicates that none of those historical brewing waters (especially the ones known for brewing great dark beers) have RA values greater than 180 ppm. Therefore, my recommendation has been that RA should generally range from 0 to 180 ppm, but I'd say that it could be fudged to about -25 to 200 ppm without ill effect.

Overall, Phil's water is a pretty good starting point for many beers and he only needs minor acid addition to brew pale beer and minor minerals to brew darker.

Martin noted a number of important points. I second the concern about the Palmer’s SRM to RA conversion which is commonly used. My research led me to a different formula and unfortunately John’s initial research data got lost and he can’t exactly say how he arrived at that formula. I incorporated my formula in my water spreadsheet : Kaiser_water_calculator.xls. The RA recommendations have also been published in tables here.

Chalk behaves rather oddly in the mash. If the 150 ppm (0.3 g per gallon) that Martin suggests are not dissolved with CO2 then they result in a residual alkalinity increase of only 33 ppm as CaCO3. Apparently not all of the acid neutralization power is realized. But if you dissolve the chalk you get a RA increase of about 110 ppm as CaCO3. I don’t know why this is but I have seen this in a number of different experiments including a side-by side batch.

Kai, you made me dig back into my water chemistry texts. Indeed, chalk solubility is improved with carbonic acid (CO2 in water), but I would have expected that the acids developed in the mash would have performed the same duty as the carbonic acid. Carbonic acid is very weak and I just assumed that the malt phytins were equal or better acids. Maybe that is not the case, based on your evidence.

Carbonate solubility can be affected by ligands and a wort solution would be full of a variety of ligands. Maybe that is another reason that the phytins don't work effectively to dissolve the chalk.

Off hand, I am going to have to agree with you that pre-dissolution of chalk in your mashing water with air bubbling may be necessary to meet our alkalinity goals. You would want to add and dissolve the chalk in room temperature water, since the solubility of CO2 is reduced as the temperature rises. I'd recommend adding the appropriate amount of chalk into the full volume of mashing water and either stir, splash, or bubble air into the water to achieve solution. This could take some time, so plan ahead.

Kai has some info on his site about making concentrated chalk water in a corny keg. I would probably do that if I was adding carbonate frequently.

I prefer to take an emperical approach. Dough-in, test pH, and if I would like it to be higher stir in some chalk. Rinse and repeat.

Since taking this approach, I find that I rarely add any chalk whether using tap water (RA=12) or RO water plus some CaCl and/or CaSO4 (modest negative RA, I never calculate it). I tend to need it on things like baltic porter, robust porter, american stout etc that are dark and do not get all of the color from roasted barley (eg not dry stout). This agrees with Kai's model which I think is likely the best published RA to SRM model. I still think that if you can measure pH none of the models are desireable (assuming what you want to do is control mash pH).

Its the weak and strong acid thing affecting the solubility. I'm assuming you're titrating with a strong acid and it has no problem dissociating the chalk solid into its ionic components.

Yes, I titrated with hydrochloric acid.

But the mash pH is about 1 pH unit lower than pka1 of carbonic acid. This means that the vast majority of carbonate should be present as carbonic acid or dissolved CO2. Only less than 10% should be bicarbonate and even less should be carbonate.

The other question, that goes along with this is how much of the chalks calcium will be dissolved in the mash when it appears that the chalk is not contributing all its acid neutralizing potential.

I have dissolved chalk with pressurized CO2 in soda bottles but since there doesn’t seem to be any downside to not dissolving it and just using twice as much I didn’t push this method as being needed to brew better beer.

astrigent, maybe somewhat tannic or on the other end of the spectrum at thin brown water.

you're trying to identify a flavor that's 3 different flavors. My feeling is that this off flavor is caused by something other than water and pH.

Maybe you could describe your process for brewing the beers in which you perceive these flavors as a starting point for finding a resolution.

Also, find a good, cheap pH meter if you're convinced that the off flavor is related to water chemistry - 0.1 resolution should be good enough to figure out if you're significantly out of range - perhaps even colorpHast strips would be granular enough to provide peace of mind in this instance.

My research of the waters from historical brewing centers and waters around the world has led me to recommend that the proper relationship between beer color and RA is approximately RA = SRM times 4.5.

I'd be cautious about recommending an RA of over 20 for a 5 SRM base malt-only Pilsner.

astrigent, maybe somewhat tannic or on the other end of the spectrum at thin brown water.

you're trying to identify a flavor that's 3 different flavors. My feeling is that this off flavor is caused by something other than water and pH.

Be careful trying to interpret someone's difficulty describing a flavor. My personal experience, and apparently a common experience among other brewers using very soft coastal waters, has been that roasty beers produced with uncorrected water are acrid, which can be confused with astringency or tannic flavors when someone is grasping for a descriptor. A common, and seemingly successful, solution has been to raise the RA. It solved my problem with these beers. A little Sodium and Chloride can help, too.

And it still puzzles me why it behaves like this. I have titrated water with dissolved chalk and here it behaves as expected. Each mole of CaCO3 adds 2 Eq of alkalinity.

I loath Carbonate chemistry with a passion and it always sends my head spinning. There are too many factors and equilibria involved. Have you included in your calculations the Bicarbonate created by dissolving CO2 in water and a possible role of the Carbonate Buffer that is created?